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aconite

(Encyclopedia)aconite ăkˈənīt [key], monkshood, or wolfsbane, any of several species of the genus Aconitum of the family Ranunculaceae (buttercup family), hardy perennial plants of the north temperate zone, gro...

ether, in chemistry

(Encyclopedia)CE5 Ethers ether, any of a number of organic compounds whose molecules contain two hydrocarbon groups joined by single bonds to an oxygen atom. The most common of these compounds is ethyl ether, C...

astringent

(Encyclopedia)astringent əstrĭnˈjənt [key], substance that shrinks body tissues. Astringent medicines cause shrinkage of mucous membranes or exposed tissues and are often used internally to check discharge of s...

button

(Encyclopedia)button, knoblike appendage used on wearing apparel either for ornament or for fastening. Although buttons were sometimes used as fasteners by Greeks and Romans, they were more often merely ornamental ...

petroleum

(Encyclopedia)petroleum, oily, flammable liquid that occurs naturally in deposits, usually beneath the surface of the earth; it is also called crude oil. It consists principally of a mixture of hydrocarbons, with t...

thrombolytic drug

(Encyclopedia)thrombolytic drug thrŏmˌbəlĭtˈĭk [key] or clot-dissolving drug, substance, such as streptokinase or tissue plasminogen activator (tPA), that causes the breakdown of blood clots (see thrombosis) ...

potassium carbonate

(Encyclopedia)potassium carbonate, chemical compound, K2CO3, white, crystalline, deliquescent substance that forms a strongly alkaline water solution. It is available commercially as a white, granular powder common...

phenolphthalein

(Encyclopedia)phenolphthalein fēˈnôlthălˈēən [key], or 2,2-Bis(p-hydroxyphenyl) phthalide, C20H14O4, crystalline organic compound. It is used medicinally as a laxative and is widely employed in the laborator...

metamorphism

(Encyclopedia)metamorphism, in geology, process of change in the structure, texture, or composition of rocks caused by agents of heat, deforming pressure, shearing stress, hot, chemically active fluids, or a combin...

sego lily

(Encyclopedia)sego lily sēˈgō [key], ornamental plant (Calochortus nuttallii) of the family Liliaceae (lily family), also known in parts of the West as mariposa lily. It is native to the region W of the Rocky Mt...